Power line communication (PLC) is a communication technology that transmits data or signals over a transmission network originally intended for power transmission or distribution. The transmission network may include a variety of transmission mediums or lines each adapted for transmitting a low, medium or high voltage over a distance within the transmission network. In order to transmit data or signal over a transmission medium or line, a PLC modem is devised and used for modulating data or signals to be sent, injecting the data or signals to be sent into a transmission medium, receiving data or signals to be read, and/or demodulating the data or signal to be read.
Although PLC technology has proven to be useful and has attracted widespread attention in a number of application areas, for example, autonomous metering architecture (AMI) networks, the implementation of this PLC technology in these application fields is not without difficulties. For example, PLC modems are traditionally located at a ground level and connected to the transmission mediums or lines that carry medium or high voltages through line couplers. The line couplers are used to isolate low-voltage communication devices from medium or high voltage transmission mediums or lines and to protect the PLC modems from surges and transients. However, these line couplers are usually expensive in both cost and implementation. Furthermore, because of the cost or absence of suitable power sources to provide low voltage for the PLC modems, installation and maintenance of these PLC modems in rural or remote areas impose extra cost and burden to an operator of the PLC modems.